Trimming machine



' Jan. 11, 1938. 'F. M. CARD 2,105,347

TRIMMING MACHINE Original Filed May 12, 1936 3 Sheets-Sheet l awe/whom fieoleric M Card wwneh mug 'Jan. 11, 1938. F. M. CARD TRIMMING MACHINE Original Filed May 12, 1936 3 Sheets-Sheet 2 [Feder wirineh WNM Jan. 11, 1938. F. M. CARD TRIMMING MACHINE Original Filed May 12, 1956 3 Sheets-Sheet 3 fiederie M Card Patented Jan. 11, 1938 STATES PATENT OFFHQE TRIMBIING MACHINE Frederic M. Card, Bridgeport, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey 9 Claims.

This invention relates to improvements in trimmer mechanisms of the reciprocating-knife type, the invention having for its primary object to provide a high-speed and durable knife-actuating mechanism in a trimming machine particularly adapted for use in the production of sharply curved and smoothly trimmed work-edges.

With the above and other objects in view, as will hereinafter appear, the invention resides in the trimming and work-feeding mechanisms described in connection with the accompanying drawings, in which:

Fig. 1 is a rear side elevation, partly in section, of a machine provided with the improved trimmer-knife actuating mechanism. Fig. 2 is an enlarged front end elevation, partly in section, of the machine. Fig. 3 is a detail View in elevation of the trimmer-knife throw-in lever. Fig. 4 is a top plan view, partly in horizontal section, of the machine and the trimmer-actuating mechanism thereof. Fig. 5 represents a substantially vertical section of the counter-shaft crank and pitman. Fig. 6 represents a longitudinal section of the crank-actuated pitman, taken substantially on the line 5-43, of Fig. 5. Fig. 7 represents a transverse section of the pitman, taken substantially on the line 'I'I, of Fig. 6.

As described in my co-pending patent application, Serial No. 79,231, filed May 12, 1936, of which this application is a division, the present invention as illustrated in the drawings is embodied in a sewing machine combining stitching and underedge trimming mechanisms. However, it is to be understood that in accordance with the present invention, the thread-handling mechanisms of the sewing machine may be omitted and that the machine may be employed solely for trimming purposes.

Referring to the drawings, the machine has a frame comprising a bed-plate I, from one end of which rises a work-supporting post 2. Upon the opposite end of the bed-plate is the supporting standard 3 of a bracket-arm 4 which terminates at its free end in a head 5 overhanging the worksupporting post 2. J ournaled in the bracket-arm i, is a horizontally disposed main actuating shaft 5 carrying at one end a combined belt-pulley and balance-wheel i.

The work to be trimmed is advanced by a feedwheel 3 projecting through a suitably slotted work-supporting plate 9 secured upon the upper end of the work-supporting post 2. The feedwhecl 8 may be rotated by any suitable actuating connections with the main-shaft 6, the present feed-wheel actuating mechanism being similar to that disclosed in U. S. Patent No. 1,884,404, Oct. 25, 1932, W. C. Van Ness et al., according to which the feed-wheel is rotated at selectively different speeds to continuously advance the work. Opposed to the feed-wheel B is a presser-roller Ill carried by the lower end of the usual spring-depressed presser-bar II journaled for vertical movements in the bracket-arm head 5.

Secured, by screws l2, to the under side of the bracket-arm 4 is a trimmer bracket i3, providing bearings in which a knife-bar I4 is journaled for endwise reciprocation in a vertically inclined path. Carried by the lower end of the knife-bar I4 is a knife-holder I5 to which a work-severing element in the form of a straight-edge trimmerknife I6 is secured by screws ll. While the cutting edge of the knife is straight, it is preferably inclined downwardly in the direction of feed, as illustrated in dotted lines in Fig. 2 of the drawmgs.

Suitably secured upon the knife-bar I4 is a collar l8 pivotally connected by a link 19 to an arm 20 of a bracket carried by the lower end of an actuator-bar 2|. The actuator-bar 2! is confined to vertical reciprocation in suitable guide-slots provided in the bracket-arm head 5, said bar 2! having in its outer edge a notch 22 adapted to receive a coupling-pin 23. The coupling-pin 23 is carried by the free end of a crank-arm 24 extending horizontally forward from one end of a rock-shaft 25 disposed substantially parallel to the main shaft 6, said rock-shaft 25 being journaled for rocking and endwise movements in bearing-lugs 26 upon the machine bracket-arm, at the rearward side thereof.

At its end opposite to the crank-arm 24, the rock-shaft 25 has a circumferential groove 21 embraced by a suitably notched ear 28 upon a trimmer throw-out hand-lever 29. The handlever 29 is pivotally mounted upon a horizontally disposed fulcrum-screw 30 extending transversely of the main shaft 6 and threaded into a boss 3| upon the machine bracket-arm 4. The handlever 29 depends below the bracket-arm 4 so as to be conveniently accessible from the front side of the machine, said hand-lever being spring biased in a direction to releasably hold the coupling pin 23 in the notch 22 of the actuator-bar 2 I. A coil-spring 32 has its opposite ends connected to the bracket-arm 4 and to the knife-bar It to retract said knife-bar from operative position and thereby to raise the actuator-bar 25 when the hand-lever 29 is operated to disconnect the coupling-pin from the actuator-bar 2|.

Suitably secured upon the trimmer-bracket l3,

at the rearward side thereof, is an auxiliary bracket-plate 33 having its upper end spaced from the bracket |3 to receive therebetween a throw-in hand-lever for the trimmer-knife. This hand-lever comprises complemental levermembers 34, 35 pivotally mounted adjacent each other upon a stud-bolt 36. The member 34 has a laterally. ofiset extension 3*! overhanging the upper end of the lever-member 35 and to this extension is suitably secured a bent spring 33 bearing against the lever-member 35 belowthe pivotal axis thereof, said spring 38 functioning to yieldingly hold the lever-members 34, 35 against relative movement. The lever-member 35 of said hand-lever is yieldingly held by a spring 33 against a fixed stop-pin 43 extending inwardly from the bracket-plate 33 and determining the normal inoperative position of the handlever' 34, 35. The offset extension 31 of the lever-member 34 is adapted to engage the upper end of the knife-bar i4 upon operation of the hand-lever 34, 35 and,ias the bent spring .38 is stronger than the spring 39, the knife-bar I4 maybe depressed by .said hand-lever until the coupling-pin '23 enters the notch 22 in the actuator-bar 2|.

However, as the throw-in movement of the knife-bar l4 serves to initiate reciprocation of the actuator-bar 2! by the rock-shaft 25, the rapidly succeeding rising movement of the knifebar M with the actuator-baril reacts against the hand-lever extension 31 before the member 35 of the hand-lever can be released by the operator. It is at this time, primarily, that the spring 38 functions to permit the member 34 of the handlever to yield relatively to the member 35, thereby absorbing the vibratory action that would otherwise be transmitted to the hand of the operator. The hand-lever member 35 is, in the present instance, provided with a headed stud 4| which serves as a steadying guide for the lower arm of the member 34 oi said hand-lever. From .the foregoing description it will be understood that the trimmer-knife carrying bar l4 may be connected to and disconnected from the rock-shaft 25 at the will of the operator during the operation of the machine.

Extending rearwardly from the rock-shaft 25 and rigidly secured thereto is a forked rockarm 42, the spaced members 43 and 44 of which are provided with'horizontally alined apertures slidably receiving a pin 45 disposed substantially parallel to the rock-shaft 25. The pin 45 has a longitudinal bore 45 preferably receiving a wick 41, said bore 45 being intersected by a plurality of radial ducts 43 provided in said pin to conduct.

lubricant to the bearing faces in the rock-arm members 43 and .44 for the pin 45.

Rigidly secured by a screw 49 upon the slidepin 35, between the rock-arm members 43, 44, is

the apertured lower end of a vertically disposed pitman 53. At its opposite end, the pitman 53 isapertured to pivotally embrace a crank-pin 5|, extending from a crank-disk 52 at one end of a rotary counter-shaft 53. The pitman 5D is restrained against movement endwise of the crank-pin 5| by a collar 54 suitably secured upon said crankpin. The counter-shaft 53 is disposed substantially parallel to the main shaft 5 and is journaled in flanged bearing-bushings 55 and 55 suitably secured in horizontally apertured lugs 5! and 53 of a bearing-bracket 53. The bracket, 59 'is secured by screws 60 upon the machine bracket-arm 4 so that the counter-shaft bearing lugs of said bracket 59 extend rearwardly from the bracket-arm 4. g

Suitably secured upon one end of the countershaft 53 is a grooved pulley 6| connected by a belt 62 to a pulley 63 carried by the rotor-shaft 64 of an electric motor 55. The electric motor 55 is mounted upon a bracket 53 secured by screws 5! upon the rearward side of the supporting standard 3 of the sewing machine bracket arm, said electric motor 55 being preferably provided with an electric-current controlling switch 58. The pulleys 5| and 53 are preferably proportioned so that the counter-shaft 53 is rotated at a lower rate of speed than the speed of rotation of the rotor-shaft 64. 7 v

Inorder to supply lubricant to the countersha'ft bearings, the bracket-lugs 51 and 58 are each provided with upstanding and vertically apertured bosses 59, the apertures I3 in said bosses (Fig, 5) being alined with lug-apertures 1| forming lubricant wells below the bushingapertures in said lugs. Each bushing 55 or 56 is diametrically apertured to provide a restricted duct 32, connecting the boss-aperture T3 with the shaft-bearing face of the bushing, and a larger duct 13 alined with the lug-well 7|. Preferably, a wick M is disposed in the well H and extends through the bushing-duct 13 into contact with the counter-shaft 53. The bossaperture 13 is yieldingly closed at its upper end by a suitable spring-pressedvalve '55, while the bushing, 55 or 56, is provided in its shaft-bearing face with intersecting spiral grooves 16. Oil introduced into the boss-aperture 13, through the valve 15, passes through the ducts I2. and 13 into the well II, from which it is conducted by the wick M to the shaft and is distributed by the bushing-grooves l6 lengthwise and circumferentially of the shaft-bearing face of the bushing.

The pitman 53 is provided longitudinally thereof with a bore 11 (Fig. 6) of which the upper end is enlarged to'form a reservoir 78 adjacent the crank-pin 5|. Intersecting the lower'pcrtion of the reservoir 18is a transverse pitman-bore i3 connecting said reservoir with the crank-pin bearing face of the pitman. Disposed in the transverse bore 19 is a wick 8D in wiping engagement with the crank-pin 5|. The upper end of the reservoir is, preferably, yieldingly closed by a spring-pressed valve 8!, while the lower end of the pitman-bore T! is alined with a radial duct 32 provided in the-tubular slide-pin 45.

Partly embracing the crank and pitman connection between the counter-shaft 53 and the rock-arm members 43, 44, is an oil-guard bracket 33 which is substantially C-shaped in vertical section, said bracket having a laterally extending shank 84' secured by screws 85 to the under side of the bracket-lug 51. The lower portion of the bracket 83 has side walls 83., thereby to provide a well for collecting lubricant thrown 01f by the actuating mechanism embraced by the bracket.

From the foregoing description, it will be understood that when the electric motor 65 is in operation, the rocker comprising the rock-shaft 25 and its crank-arms 24 and 42 is continuously actuated, the reciprocation of the trimmer-knife it being dependent upon whether or not the coupling pin 23 is in operative engagement with the actuator-bar 2|. By swinging the hand-lever 29 to the right, as, viewed in Fig. 1, the rockshaft 25 is shifted endwise to disconnect the coupling-pin 23 from the actuator-bar 2|. The slide-pin 45 connection between the pitman and the rock-arm 42 leaves the pitman 501maffected by the endwise movements of the rockshaft 25. It will be further understood that the trimmer-knife l6 may be rendered inoperative by disconnecting the electric motor from its source of power, whereby the machine may be operated to advance the work without actuatin any portion of the trimmer mechanism.

Having thus set forth the nature of the invention, what I claim herein is:-

l. A trimmer mechanism. com-prising, a reciprocatory trimmer-knife actuating bar, a rocker shiftable lengthwise of its pivotal axis into and out of operative engagement with said bar, manually operable means for axially shifting said rocker, a rotary shaft, a crank-member carried by said shaft, a pitman embracing and restrained against movement axially of said crank-member, and an axially shiftable pivotal connection between said pitman and said rocker.

2. A trimmer mechanism comprising, a reciprocatory trimmer-knife actuating bar, a rocker shiftable lengthwise of its pivotal axis into and out of operative engagement with said bar, manually operable means for axially shifting said rocker, a rotary shaft having its axis of rotation substantially parallel to the pivotal axis of said rocker, a crank-member carried by said shaft, a pitman embracing and restrained against movement axially of said crank-member, and an axially shiftable pivotal connection between said pitman and said rocker.

3. A trimmer mechanism. comprising, a reciprocatory trimmer-knife actuating bar, a rock-shaft shiftable lengthwise of the pivotal axis thereof, manually operable means for axially shifting said rock-shaft, a crank-arm carried by said rock-shaft adapted to be coupled to and disconnected from said bar, a rotary shaft disposed substantially parallel to said rock shaft, a second crank-arm carried by said rockshaft, and means for actuating said rock-shaft from said rotary shaft including an axially shiftable pivotal connection with said second crankarm.

4. A trimmer mechanism comprising, a reciprocatory trimmer-knife actuating bar, a rotary shaft, a crank-member carried by said shaft, a plural-armed rocker having one of its arms op eratively connected to said actuating bar, a pitman carried by said crank-member, a slide-pin carried by said pitman and having a sliding pivotal connection with another arm of said rocker, and manually operable means for shifting said rocker lengthwise of the pivotal axis thereof, thereby to disconnect said rocker from said actuating bar.

5. A trimmer mechanism comprising, a reciprocatory trimmer-knife actuating bar, a rotary shaft, a crank-member carried by said shaft, a rocker operatively connected to said actuating bar and having a forked crank-arm provided with alined bearing apertures, a pitman embracing said crank-member and provided with a lubricant reservoir open to the crank-member, a tubular slide-pin carried by said pitman in pivotal and endwise sliding engagement with said crankarm, said slide-pin having radial ducts connected with said reservoir and with said crank-arm bearing apertures, and manually operable means for shifting said rocker lengthwise of the pivotal axis thereof, thereby to disconnect said rocker from said actuating bar.

6. A trimmer mechanism comprising a reciprocatory trimmer-knife actuating bar, actuating mechanism for reciprocating said bar adapted to be operatively connected to said bar during the operation of said mechanism, and manually operable means for operatively connecting said bar and its reciprocating mechanism including a hand-lever having members yieldable relatively to each other responsive to reciprocation of said bar by said mechanism.

'7. A trimmer mechanism. comprising a reciprocatory trimmer-knife actuating bar, actuating mechanism for reciprocating said bar adapted to be operatively connected to said bar during the operation of said mechanism, and manually operable means for operatively connecting said bar and its reciprocating mechanism including a hand-lever having complemental lever-members supported for turning movements about a pivotal axis common to said lever-members, and a spring yieldingly holding said lever-members against relative movement.

8. A trimmer mechanism comprising a recip rocatory trimmer-knife actuating bar, actuating mechanism for reciprocating said bar adapted to be operatively connected to said bar during the operation of said mechanism, a member manually operable to couple said bar and its actuating mechanism, and means interposed between said member and said bar yieldable responsively to reciprocation of said bar by said mechanism.

9. A trimmer mechanism comprising a reciprocatory trimmer-knife actuating bar, an actuating element adapted to be operatively connected to reciprocate said bar, means for shifting said bar into position for engagement by said actuating element including a manually operable member, and means yieldingly interposed between said member and said bar.

FREDERIC M. CARD. 

